A potentially Earth-like planet may lose its atmosphere

The researchers claim that the planet TRAPPIST-1e, which has previously been recognized as potentially habitable, may have problems with the atmosphere. Electric currents in its upper layers can lead to heating and expansion of gases, which can be dispersed in space. 

The artist’s concept of TRAPPIST-1e. Source: www.artstation.com


American scientists have published a study in The Astrophysical Journal, according to which processes can occur on the exoplanet TRAPPIST-1e, as a result of which gases in its atmosphere can expand and disperse into space. As a result, it may lose them completely.

TRAPPIST-1 is a fairly cool red dwarf that is 41 light-years away from us, which is not far away. At the time it became extremely famous due to the fact that seven planets orbit around it, which are close in size to Earth or Mars. Three of them are located in the star’s life zone.

At the same time, TRAPPIST-1e is located at a distance of 0.028 AU from its star, which is much smaller than the orbit of Mercury. However, due to the fact that the star is a red dwarf, the conditions on it should be quite habitable.

The density of TRAPPIST-1e is 2 percent higher than that of Earth. At the same time, it is slightly smaller than our planet, therefore, the gravity on its surface is 82 percent of what we are used to. The average temperature on the surface of this world is 246 K, which is only 9 less than on Earth.

Planet’s atmosphere

High-energy particles flying from the star can potentially destroy any atmosphere of the planet if they knock out molecules from it for millions of years. However, worlds that resemble Earth in their characteristics should have a powerful magnetic field that protects them from this.

At the same time, TRAPPIST-1e is much closer to its star than Earth and the intensity of the solar wind there is much greater. It has already been proven that despite the presence of magnetic fields, the planet would not hold the primary atmosphere of hydrogen. However, this only means that most likely its gas shell consists of something else.

The authors of the new study had previously suggested that, under certain conditions, powerful electric currents can occur in the atmospheres of planets e, f and g, which heat gases even more strongly than the harsh ultraviolet radiation of a star.

Now, the authors have established that another mechanism for the occurrence of currents is possible — due to the movement of the planet around the star. In this case, the magnetic fields of the body and its parent star interact. Scientists suggest that both mechanisms work on TRAPPIST-1e. Therefore, it really could have lost all its atmosphere long ago, although these assumptions are based on some untested facts.

According to phys.org

Follow us on Twitter to get the most interesting space news in time